You know exactly how much torque the motor is producing based on input power, specs of the motors, and torque/radius of the wheel=Force. If you know torque and you know the weight on that wheel (because the rivian has air suspension it does) you can go back to the formula and find how much power you can put down with that weight and then once the motors detect slip (milliseconds for electric motors) it can find friction of the surface because it knows how much it took to overpower it, it knows what the torque limit is because it just found it and because it can adjust its power hundreds to thousands of times per second (as compared to the 5-10 or so of ICE) it can constantly stay on that limit.
Iâm sure you can see the problem with implementing this in esk8, we donât have air suspension so we donât know weight per wheel which is what makes this work. For our purposes, wheel speed measurements would be fine, there is no reason we need to calculate Fr, âif itâs slipping back off powerâ is going to accomplish 99% of the same thing for us. The rivian is like that so it knows what surface its on for off road or snow so it can adjust the rest of the car including braking suspension etc, thatâs all useless to us and there is no reason to go through all that work.
hehe⌠yes i was already thinking that the surface fr is not necessary and does not bring any advantage in esk8 case.
so basically, as you say, a simple âESPâ on each wheel would be the biggest step 
but that brings me back again to that question, âwhy this is not already implemented in vescââŚ
Idk, ask them:
FR though My guess is that it can be with lisp scripting but probably requires an encoder on each drivetrain
thanks for the invitation.
I just overviewed the channel and there are multiple discussions about this. hehe⌠also the very latest entry is about traction control for a motocross bike. also talks about the implementation in lisp.
but to be honest, I probably have to learn and think more about this topic until I know what to do
its not only traction control what we want. its also overpowering the outer wheels and balancing rear to front⌠have to sort that out, hehe.
thx for now.
I dont want to spam this thread too much.
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This is not definitely not spamming the thread
They havenât even figured out how the enter or tab key works. I wouldnât hold out.
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Donât start by trying to emulate state-of-the-art automotive traction control. Instead, just look at what inputs are available and interesting, what outputs are available and interesting, and simple strategies for using those inputs to modify those outputs.
Some interesting inputs:
wheel speeds
lateral acceleration
roll angle
yaw rate
The outputs are of course the power to each wheel - but if the goal is to stabilize the yaw rate then itâs probably useful to also think of it in terms of total power and left-right power bias.
Active yaw control strategy:
Use speed + roll angle to calculate a desired yaw rate. Subtract that from the actual yaw rate and you have a âyaw errorâ value. The simplest thing you could do is multiply that yaw-error by a constant and use the result for the left-right power bias. Tune the constant until the stability control feels about right.
You could get more fancy about it by using a lookup table with âactual yawâ on one axis and âdesired yawâ on the other, with the table cells containing the power bias - that would give you the ability to make the power bias get stronger or weaker in a nonlinear way.
You could get even more fancy about it by scaling the left-right bias by the current speed, either with a simple proportional constant or with another lookup table.
Traction control strategy:
Average the wheel speeds to compute your total speed.
If any wheel starts to spin more than X% faster than the others, assume that itâs slipping, and reduce the power to that wheel by Y%, where Y is proportional to the speed difference for that wheel. Periodically multiply the value of Y by Z (for example, 0.95) every 10ms so that the torque reduction tapers off over time.
Tune X so that this doesnât kick in during tight turns. Tune Y so that the torque reduction is enough to fix wheel spin but small enough to not be too intrusive. Tune Z so that the torque reduction tapers off slowly enough to be effective but fast enough to not be too intrusive.
With any luck, the same math will also work in reverse to provide anti-lock braking.
Neither of those is perfect, but neither one needs to be perfect to be useful. It just needs to be better than nothing. With some time to tune and troubleshoot we can find their biggest shortcomings and find ways to address those shortcomings. Or come up with completely different approaches.
But we definitely shouldnât be paralyzed by the fact that more sophisticated approaches exist. Just start simple and iterate.
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Just having pitcrews would be fun lol. have a lil jack and two dudes run up on you change ur batteries and shove you off all nascar style?!
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Didnt realize the DMV had esk8s as well. I pnly started seeing Onewheels and maybe a custom board in the coming months. If ESK8 racing gets off big the east vs west coast and midwest in between would be a crowd pleaser to say the least
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Two jacks
Fresh tyres
Leaf blower cooling motors
Fresh battery
Clean visor
Hydration
Thats what around 10 people required? Sounds like something to work towards 
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I feel like 6 people with enough practice could get that under 0.5s
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So thatâs 4/21 9pm PST right?
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2023-04-22T04:00:00Z
This seems to be converting to localtime for me the viewer. 
My first attempt at using the discourse âinsert dateâ
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Definitely more events. The âundergoroundâ carpark meets are fun. But just not appealing for a lot of people as they need to be done late at night.
More sanctioned events needed for sure across the world.
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Sanctioned by whom?
There needs to be more independent events and more companies willing to sponsor them.
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Sanctioned Event means an event, tournament, and/or matches conducted by an authorised Event Organizer that have received formal approval
I think it just means legit. like none of it is illegal, thereâs an agreement with the venue, doesnât violate local laws. if the venue were a public roadway, park, etc. sanctioned by the city with permits and junk, etc.
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